Catherina Burghart

A cognitive architecture for a humanoid robot: a first approach

Future life pictures humans having intelligent humanoid robotic systems taking part in their everyday life. Thus researchers strive to supply robots with an adequate artificial intelligence in order to achieve a natural and intuitive interaction between human being and robotic system. Within the German Humanoid Project we focus on learning and cooperating multimodal robotic systems. In this paper we present a first cognitive architecture for our humanoid robot: The architecture is a mixture of a hierarchical three-layered form on the one hand and a composition of behaviour-specific modules on the other hand. Perception, learning, planning of actions, motor control, and human-like communication play an important role in the robotic system and are embedded step by step in our architecture

Distributed Modular Computer-Integrated Surgical Robotic Systems: Architecture for Intelligent Object Distribution

This paper presents intelligent object distribution architecture to maximize the performance and intelligence of a distributed surgical robotics system and its preliminary implementation in an MR-guided surgical robot system in an open-configuration MRI scanner. The method enables networked integration of a robot control server and multiple clients with minimum engineering overhead but maximum flexibility and performance. The clients in this study include an intraoperative imager, high-performance image processing computer(s), and surgical navigation host. The first contribution of the paper is to propose the use of object distribution by common object request broker architecture (CORBA), in which a robot control object on the robot control server can be remotely but transparently invoked from the clients regardless of their hardware, operating systems, or programming language. Second, we propose a technique to achieve additional flexibility by reporting the robot configuration information, i.e. geometry and kinematics of the robot, to the clients upon connection. Third, we ensure protection against an unauthorized entity by introducing a security control host that authorized the clients’ access to the robot server. In a prototype implementation of an MR-guided surgical robot system, the robot was controlled by surgical navigation software (the 3D Slicer) on a UNIX client by invoking the distributed control object on a robot control server on a PC. The method was evaluated in performance studies; and the result indicated 3.6 milliseconds for retrieving positions of the robot stages and 25.5 milliseconds to send a frame-based motion command, which are satisfactory for surgical robot control. In conclusion, the proposed method shows the potential usefulness of flexibly integrating the legacy software to a surgical robot system with minimum engineering overhead, thereby achieving highly complex and intelligent tasks in robot-assisted surgery.

Surgical Robotics: An Introduction

Surgical robots assisting surgeons during operations are being used in selected medical fields like neurosurgery, orthopaedics and endoscopy. In an introductory part, the authors present a workflow for robot assisted surgery, which includes the steps: image data acquisition, image processing, surgical planning and the actual robot assisted intraoperative transposition. Each step of the workflow comprises different computer aided methods and apparatuses, which are presented in this paper. The following part focuses on different mechanical set-ups and various application fields for surgical robots. They include neurosurgery, orthopaedic surgery, radiosurgery and radiotherapy, prostatectomy, endoscopy, laparoscopy, cardiac surgery and craniofacial surgery.

Integrating a flexible anthropomorphic, robot hand into the control, system of a humanoid robot

Abstract This article presents the approaches taken to integrate a novel anthropomorphic robot hand into a humanoid robot. The requisites enabling such a robot hand to use everyday objects in an environment built for humans are presented. Starting from a design that resembles the human hand regarding size and movability of the mechatronical system, a low-level control system is shown providing reliable and stable controllers for single joint angles and torques, entire fingers and several coordinated fingers. Further on, the high-level control system connecting the low-level control system with the rest of the humanoid robot is presented. It provides grasp skills to the superior robot control system, coordinates movements of hand and arm and determines grasp patterns, depending on the object to grasp and the task to execute. Finally some preliminary results of the system, which is currently tested in simulations, will be presented.

Ein Robotersystem für craniomaxillofaciale chirurgische Eingriffe.

Zusammenfassung. In industriellen Anwendungen bewähren sich Roboter durch ihre hohe Präzision und Wiederholgenauigkeit. Ihr Einsatz in neuen Gebieten, wie z.B. in der Chirurgie unterliegt aber anderen Randbedingungen. Die Datenakquisition und Planung jedes Eingriffs muß individuell für einen Patienten ausgeführt werden. Die präoperative Planung einer Operation auf den komplexen Freiformflächen des Patienten ist nur mit der Unterstützung eines rechnerbasierten Planungssystems durchführbar. Durch eine integrierte intraoperative Instrumentennavigation wird sichergestellt, daß die geplanten Vorgänge auch geometrisch richtig ausgeführt werden. Eine prototypische Roboterarbeitszelle dient zur Evaluierung der untersuchten Methoden und entwickelten Subsysteme. Die vorgestellten Arbeiten finden im Rahmen des Sonderforschungsbereiches 414: “Rechner- und sensorgestützte Chirurgie” statt, der eine enge interdisziplinäre Zusammenarbeit zwischen Ingenieuren, Medizinern und Naturwissenschaftlern ermöglicht.Abstract. In industrial applications robots prove successful due to their high precision and their repetition accuracy. However, when used in new fields, e. g. in surgery, other conditions apply. The acquisition of data and the planning of each operation must be carried out individually for a patient. The preoperative planning of an operation on the complex free forming surfaces of a patient can only be realised with the support of a computer based planning system. An integrated intraoperative instrument navigation ensures that the planned proceedings are performed geometrically correct. A prototypical robot cell evaluates the examined methods and developed subsystems. The presented studies are carried out within the framework of the Sonderforschungsbereich 414 “Computer and sensor supported surgery” which allows a close interdisciplinary cooperation between engineers, doctors and scientists.

A device guidance method for organ motion compensation in MRI-guided therapy

Organ motion compensation in image-guided therapy is an active area of research. However, there has been little research on motion tracking and compensation in magnetic resonance imaging (MRI)-guided therapy. In this paper, we present a method to track a moving organ in MRI and control an active mechanical device for motion compensation. The method proposed is based on MRI navigator echo tracking enhanced by Kalman filtering for noise robustness. We also developed an extrapolation scheme to resolve any discrepancies between tracking and device control sampling rates. The algorithm was tested in a simulation study using a phantom and an active mechanical tool holder. We found that the method is feasible to use in a clinical MRI scanner with sufficient accuracy (0.36 mm to 1.51 mm depending on the range of phantom motion) and is robust to noise. The method proposed may be useful in MRI-guided targeted therapy, such as focused ultrasound therapy for a moving organ.

Co-operative carrying using pump-like constraints

In this paper we present a new method for the cooperative carrying of a rigid object by a robot and a human. This method is based on tactile sensor input. In the carrying mode the robotic system defines constraints for the users possible movements when manually guiding the object (and robot arm). Thus, instead of using a complex recognition process for interpreting the users intention the robot determines the next action on basis of the defined constraints and the measured tactile sensor data. The defined constraints only allow the human partner to manipulate the carried object during the carrying procedure in the manner of a water hand pump. In this way, so-called in-place-translations of the object in all directions are possible, while the human partner maintains full control over orientation and position of the object.

Robot cell for craniofacial surgery

Using a robot in craniofacial surgery might seem to be a rather far fetched idea. However, a high level of precision, skill and experience is necessary in order to perform maxillofacial interventions successfully and harmonically. Thus the Institute of Process Control and Robotics has devised a complex computer aided surgical system which supports the surgeon before and during the operation. On the one hand preoperative plans can be generated by using a three-dimensional computer model of the patients skull. On the other hand the best planning device is rather useless if there is no adequate means at hand to intraoperatively transpose the established plan with the required accuracy. In this paper we present our surgical robotic system for craniofacial surgery and give an insight into some of its features.

Coding interaction patterns between human and receptionist robot

Intelligent robotic systems will be found in several fields of everyday life in the near future. This implies an easy handling of an interaction with service robots by naive persons. Up till now many problems in human-robot interaction do exist; one of them is the great variety of human communication and behavior. Thus system designers often cannot anticipate human behavior which leads to frustrated users. We have devised a tool to analyze and code human and robot behavior during human-robot interaction, which can serve as a first stepping stone toward recognizing, automating coding and adapting robot behavior in order to obtain successful interactions. The tool called Interaction Analysis Protocol was used in different interaction scenarios between robot and human being. In this paper we present an experiment within which the robot acts as receptionist. The analysis and coded behaviors are based on the Interaction Analysis Protocol.

Integriertes Patientenmodell für chirurgische Eingriffe

Die praoperative Modellierung des individuellen Patienten bzw. seiner fur die Operation relevanten Aspekte bildet die Grundlage fur die Automatisierung von Vorgangen im Operationssaal. Insbesondere der Einsatz eines Roboters bei chirurgischen Eingriffen ist ohne diese Daten nicht moglich. Haufig existieren verschiedenste Daten uber einen Patienten; sehr oft in nicht kompatibler Form und sie erfullen nicht die spezifischen Anforderungen chirurgischer Modelle. Im folgenden wird ein Ansatz fur ein integriertes Patientenmodell vorgestellt, das sich im Moment auf Anforderungen der Mund-, Kiefer- und Gesichtschirurgie beschrankt.